Rahul, often mistaken as filmmaker Mahesh Bhatt's son, will be seen in the lead role in Kashyap's film.
Talking about the mystery over his looks in the film, a source said: "Anurag has asked him to be under house arrest since his look and character is the film's surprise element. He has been kept away from media and has kept the media guessing about his role and character in the film."
The actor, who was seen in films like "Nayee Padosan" and "Yeh Mohabbat Hai", will be seen on the big screen after a gap of nine years.
"I have always wanted to work with Anurag and I am glad to be a part of this film," Rahul said in a statement.
Talking about his lead actor, Kashyap said: "I have known Rahul since my struggling days when we lived next door. I discovered his potential much later after I started interacting with him. His life experience is quite close to what I have written for my character."
The film will be screened in Directors' Fortnight section at 66th edition of the Cannes International Film Festival, starting May 15.